1. Field of the Invention
This invention relates generally to a ring-shaped mold and the method and the apparatus for making the same, and more particularly to a ring-shaped mold of the split mold type constructed by assembling into an annular shape a plurality of sectorial separate blocks formed by centripetally cutting a ring-shaped workpiece by means of a cutting device using a wire cutting tool and the method and the apparatus for making the same, wherein a set for a ring-shaped mold can be manufactured from a single ring-shaped workpiece due to small cutting allowances resulting from the use of the wire cutting tool.